Re: The best place to begin learning Assembler

On 5/26/2010 3:14 PM, Ron Hudson wrote:
> Ok, I have the PDF of the 370 Principals of Operations (Sept) and the
> Instruction Overview from SimoTime
>
> (I noticed AR and ALR seem to be the same instruction??)
>
> Where, apart from these references, is the best place to learn Assembly?

If you consider AR and ALR the same instruction, then your 
effort is doomed from the start. AR sets a condition code, ALR 
does not. If R0 contains 1, and R1 contains x'7FFFFFFF' and you 
do ALR R1,R0, you get x'80000000'; if you did AR R1,R0 you would 
get a surprise (depending on the program mask setting).

There are a few good books on e-bay every once in a while, but 
the better ones are very expensive. One way of learning is to 
use ASSIST, which takes care of some basics (input, output) so 
you can concentrate on the instructions. Others have gone to the 
CBT files (distributed with tk3; also on www.cbttape.org), 
picked one or more interesting programs, and analyzed them until 
they understood what they did. It depends on your learning 
style. But beware - there are many purported assembler books out 
that not worth the paper they're printed on.

And there is always google to lead you to mysterious 
destinations <g>



Gerhard Postpischil
Bradford, VT